convection column: rising column of gases, smoke and other debris produced by a fire

creeping: fire burning with a low flame and spreading slowly; also called skunking

crown fire: a fire that moves from the top of one tree or shrub to another; which can move independently of the fire activity on the ground

dirty burn: an area where there is still a lot of standing, half-burned fuel susceptible to reburning

flare-up: a brief acceleration or intensification of fire that does not change fire-control plans; compare blow-up

hot spot: a particularly active part of a fire

plume-dominated fire: fire with behavior dominated by the convection column that can spread in any direction because the fire will pull burning debris into the column and spit it out anywhere

running: fire that is spreading rapidly with a well-defined head

skunking: fire burning with a low flame and spreading slowly; also called creeping

sleeper fire: fire started by lightning strikes that go underground and erupt several days or weeks later from wind or hot, dry conditions; also called holdover fire

a smoke: evidence of a new fire, often after a lightning strike (colloquial)

smoldering: fire burning without flame and barely spreading

spotting: starting new fires outside the perimeter by sparks or embers carried by the wind

torching: burning of foliage of a tree or small group of trees from the bottom up; depending on the number of trees involved, may be described as single or group torching

Control and suppression

anchor point: a barrier from which to start building a fire line

burnout: a tactic that involves burning the area between an established control line some distance from the fire and the main fire; sometimes called backburn or backfire, but the official term is burnout

containment: a control line completed around the fire and associated spot fires that can be expected to stop the fire from spreading

control line: an inclusive term for all constructed or natural barriers used to contain a fire

control: completion of a control line around the perimeter, spot fires and interior islands; burnout of unburned areas adjacent to the control lines; cooling of all hot spots

coyote tactics: use of spike camps; also called coyoting

direct attack: establishing a control line on the perimeter of the fire by digging down to mineral soil

fire line: a control line scraped or dug to mineral soil; there are hand lines (dug with shovels) and dozer lines (dug by bulldozers)

hot shots: highly trained fire crews used mainly to build fire line by hand, often in rugged terrain

indirect attack: establishing a control line some distance from the main fire, either by digging a line or using a natural barrier such as a road or river

management action points: geographic points on the ground or specific points in time that guide fire management; also called trigger points

mop-up: extinguishing or removing burning material near control lines and felling snags to make an area safe after it has burned

patrol status: going back and forth over a control line to suppress spot fires and extinguish hot spots

point protection: specific structures or communities identified for protection

spike camp: where firefighters stay to work on a fire when it is far from roads or involves a long hike; a line spike camp refers to a camp on the fire line

Fuels

jack-strawed trees: trees scattered like toothpicks, generally from a windstorm

ladder fuels: surface fuels such as needles or leaves, and shrubs and lower branches that provide a path for the fire to move from the ground to the tree canopy

light, flashy fuels: dry grasses and shrubs

Weather

Haines index: measures the stability and dryness of the air over the fire to indicate the potential for wildfire growth; the index ranges from 2 to 6—the drier and more unstable the lower atmosphere is, the higher the number

Other terms

defensible space: an area around a house cleared of flammable vegetation and other potential ignition sources and kept well-maintained and watered

Sources: National Wildfire Coordinating Group Glossary of Wildland Fire Terminology, a glossary on WildlandFire.com, and interviews with public information officers from the incident management teams and local firefighters.